android - ListView does not show changes until focus changes after notifyDataSetChanged -

i have alertdialog listview set multiple selection on it. has button on it.

the button open alertdialog if ok'ed remove selected items data set of listview, , tell adapter of list view dataset has changed notifydatasetchanged() method.

this works fine except 1 thing. listview not update it's content until interact something. updates correct data.

this not big problem, listview appear correct @ once, , not after focus has changed.

code:

button remove = (button) view.findviewbyid(r.id.btn_remove_questions_edit_rack);     final context con = this;     remove.setonclicklistener(new onclicklistener()     {         @override         public void onclick(view v)         {             builder warnbuild = new builder(con);             warnbuild.setmessage(r.string.question_deletion_warning);             warnbuild.setpositivebutton(r.string.ok, new dialoginterface.onclicklistener()             {                 @override                 public void onclick(dialoginterface dialog, int which)                 {                     sparsebooleanarray checked = list.getcheckeditempositions();                     (string s : keys)                     {                         int = keys.indexof(s);                         if (checked.get(i))                         {                             toremove.add(map.get(s));                             map.remove(s);                         }                     }                     keys.clear();                     keys.addall(map.keyset());                     ((arrayadapter) list.getadapter()).notifydatasetchanged();                     list.clearchoices(); //this makes sure selection cleared, if isn't, of other items (those has index of selected items) selected when view refreshes.                     dialog.dismiss();                 }             });              //negative button here, not relevant.         }     }); 

where map , keys are:

final hashmap<string, qualityquestion> map = new hashmap<>(); //i add items map final arraylist<string> keys = new arraylist<>(map.keyset()); 

and toremove store items removed actual object on when ok button on original alertdialog pressed.

this how populate listview in first place:

final listview list = (listview) view.findviewbyid(r.id.list_questions_edit_rack);     list.setadapter(             new arrayadapter<string>(this,                     android.r.layout.simple_list_item_activated_1,                     keys)); 

i have tried things list.invalidateviews(), list.invalidate , other things found in questions similar mine here on so. none of made difference. suspect problem different theirs since items updated, takes change of focus on original alertdialog change visible.

how can make listview show changes in it's data source imidiatly insted of after focus change?

by calling

((arrayadapter) list.getadapter()).notifydatasetchanged(); 

you fresh adapter not identical anonymous adapter used populate list in first instance.

see documentation listview.getadapter()

returns adapter in use in listview. returned adapter might not same adapter passed setadapter(listadapter) might wrapperlistadapter.

from point of view of fresh adapter, data set hasn't changed because changes happened way before instantiated.

to solve problem, make list , list adapter members of activity class (or scope want keep them alive):

private arraylist<string>    keys; private arrayadapter         myadapter; private listview             list; 

then in "oncreate()"

keys = ...;     // initialization of arraylist needed data  myadapter = new arrayadapter<string>(this,                     android.r.layout.simple_list_item_activated_1,                     keys); list = (listview) view.findviewbyid(r.id.list_questions_edit_rack); list.setadapter(myadapter); 

this way, in "onclicklistener" can notify "myadapter":

keys.addall(map.keyset()); myadapter.notifydatasetchanged(); 

hope helps :)